LOGBOOK W02 by Peiyi Wang

WEEK 2 LOGBOOK

W02

01_STUDIO REPORT Process of Constructing

This weeksâ&#x20AC;&#x2122; task was to build a frame structure that was about 1.5 meters long and only use a 600mm*100mm piece of balsa (Figure 1). The structure needed to

Figure 2: Primary design 1 structure, while luckily we found out the reason in the end, and here is the comparison between our work and the real purpose:

be stable enough to support the load provided by tutor.

Our first plan was to build a structure utilizing the concept of bracing because triangle could let the structure become more stable as it is the only rigid shape. Therefore, the calculation about the total length were made. While for the joint sections in that structure, we decided to mainly use the tapes. Figure 2 and 3 is the primary design.

1.The structure should be rotated for 90 degrees:

Our structure is like Figure 4, which is actually a piece parallels to the ground, and the length between these two beam was very large that leads to a very soft structure. If we turned the structure for 90 degrees from Figure 5

Because of multiple reasons, such as miscalculating the total length, the time was not enough, we had to change the plan and use mainly pins.

But the structure still not fits the

Figure 1: Material and equipments of this task

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Figure 3: Primary design 2

Figure 4: The structure that parallels to the ground

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(Incorrect) to Figure 6 (correct), the load path will be like Figure 7, which is the ideal situation. In this case, the setting of bracing could help to transfer the force effectively. However, Figure 9: The rotation happens on the structure while a force is acting on it Figure 7: Load path diagram in a bracing

Figure 6: The correct position

Figure 5: The incorrect position

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the biggest problem was if forces were acting on that structure, because the width was too small, the whole structure would tend to rotate. This is due to that every external force has a X component and a Y component (Figure 8), when it is applied to our structure that the actual Figure 8: The X and Y contacting area components of a force is very small, the structure will

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rotate towards the direction of X component (Figure 9). Consequently, I designed another structure after the studio which might handle this problem (Figure 10).

Figure 10: New design after the studio 2. It was not a good idea to use to much pins:

Balsa piece is very fragile, and high frequency of using pins also aggravated this weakness. As a result, our work was broken just after we finished it (Figure).

This remained me that choosing material was definitely an important procedure, because material could improve the quality of an architecture a lot if choosing the suitable one (Figure 11).

efficiency will be. Because our structure was not stable at all, the efficiency was very low. In order to be more efficient, one good suggestion is to utilize more bracing, shear panel, rigid joints or portal frame, which are all ways to let and beam and column structure become more stable (M. Irving, personal communication, August 8 , 2014).

Comparison with other groups: This group made the same mistake as we do, the put the structure in a wrong position which actually did not use the bracing to transfer the load. What they did well was they set a small width between to beams (Figure 12).

Although this group put the structure in a right direction, the irregular construction of bracing may let the middle part become the target of loads and easily to be broken. And they also used a lot of pins (Figure 13).

Figure 12: Another structure in the studio (1)

Figure 11: Broken balsa due to the use of too many pins Figure 13: Another structure in the studio (2); area inside the circle is the weakest part of this design

Material Efficiency: The goal of this task was to build a stable structure under the precondition of satisfying the length requirement. So the more stable the structure is by using same amount of material, the higher

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02_LEARNING LOOP Pre-Learning • Structural System: 1. Solid Structure: Ancient structure, related with mud, bricks, etc; the main structural action is compression, arches are efficient elements; 2. Surface Structure: Sydney Opera House; 3. Skeletal Structure: most common structure in nowadays, use the frame system which has a very efficient way to transfer loads; 4. Membrane Structure: cover large area with small expense; 5. Hybrid Structure: the combination two or more structures (envs10003, 2014).

• Construction System: 1. Structural System: to support and transfer loads, includes superstructure that is above the ground and substructure that is the foundation; 2. Enclosure System: the outside of the building, include roofs and façades； 3. Mechanical System: provide services to the building;

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4. Other factors: performance requirement, Aesthetic Qualities, Economic Efficiency, Environmental Impacts(envs10003, 2014).

• ESD and Selecting Materials: 1. Environmental sustainable design (to consider the impact of the building on environments, like the energy consumption and use of natural lights, etc.)(envs10003, 2014). 2. Common ESD strategies: local material, material efficiency, water recycling, thermal mass, solar energy, water harvesting, etc (envs10003, 2014).

• Structural Joints: connection of two material 1. Roller Joints: can only resist loads from one direction, Figure X; 2. Pin Joints: could resist loads from two directions, Figure X; 3. Fixed Joints: no rotation will occur in this case, can resist a lot of loads, Figure X (envs10003, 2014).

• Framework for Analyzing Form - Column & Wall: clear stone piece on the wall could be observed which represents the structure and construction; - Point & Plan: from point to line to plan and finally to volume (from 1d to 3d), the structure could not be observed simply (envs10003, 2014).

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Studio • Timber: 1. Softwood is coming from predominately evergreen trees (Ching, 2014), or from plantation, and it is mainly used for framing or constructing (M. Irving, personal communication, August 8 , 2014). 2. Hardwood comes from broad-leaved flowering trees (Ching, 2014), or from old forest and it is mainly used for furnitures (M. Irving, personal communication, August 8 , 2014). • Timber can bear more shear forces in the direction perpendicular to its grain (Ching, 2014).However, more tension and compression forces could be loaded on the direction paralleled to the fabric than perpendicular to it (Ching, 2014). • The longer the beam is, the heavier the self weight will be, the deeper the beam should be constructed (M. Irving, personal communication, August 8 , 2014). • Method to make the ‘beam and column' structure stable: Bracing Shearing Panel Rigid Joint Portal Frame (M. Irving, personal communication, August 8 , 2014). Triangle is the only rigid shape, it • cannot move unless to break it. (M. Irving, personal communication, August 8 , 2014)

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03_GLOSSARY APPENDIX

a c

• Bracing: A way to stabilize the column and beam structure, shown in Figure 14a (M. Irving, personal communication, August 8 , 2014). • LVL：Laminated Veneer Lumber, because timber is weak in the fabric direction, therefore LVL is design as shown in Figure 15 (M. Irving, personal communication, August 8 , 2014). • Column: is a constructing element that is regis and relatively thin, which is used to support the compression forces exerted on its ends (Ching, 2014). • Fixed Joint: A kind of structural joints that can resist loads from every direction, shown in Figure 16c (envs10003, 2014). • Frame: a joint that is used to connect beam and column and can producing resisting force to both active forces and moments (Ching, 2014). • Pin Joint: A kind of structural joints that can only resist loads from two direction, shown in Figure 16b (envs10003, 2014). • Portal Frame: A way to stabilize the column and beam structure, shown in Figure 14d (M. Irving, personal communication, August 8 , 2014).

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Figure 14:

b d

Figure 14b (M. Irving, personal communication, August 8 , 2014). •Structural Joint: A structure used to connect two separate materials (envs10003, 2014). •Tension: is the result of a structure member when external force pull it (Newton, 2014). •Truss: is a structural member that use geometry and has a hollow inside to

Figure 15

•Rigid Joint: A way to stabilize the column and beam structure, shown in Figure 14c (M. Irving, personal communication, August 8 , 2014). •Roller Joint: A kind of structural joints that can only resist loads from one direction, shown in Figure 16a (envs10003, 2014). •Shearing Panel: A way to stabilize the column and beam structure, shown in

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Figure 16: a c b

increase the stability, as shown in Figure 18 (M. Irving, personal communication, August 8 , 2014).

• UB/UC: Universal Beam and Universal Column M. Irving, personal communication, August 8 , 2014).

• Web: is a connecting member of upper and lower parts, shown in Figure 19 (M. Irving, personal communication, August 8 , 2014).

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Figure 18

Figure 17

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04_REFERENCE LIST

Ching, F. (2014). Building Construction Illustrated (5th ed.). Hoboken, New Jersey: John Wiley&Sons. Envs10003. (2014a, March 9). ESD and Selecting Materials [Video file]. Retrieved from https://www.youtube.com/watch? v=luxirHHxjIY&feature=youtu.be Envs10003. (2014b, March 9). Framework for Analysing Form [Video file]. Retrieved from https://www.youtube.com/watch? v=KJ97Whk1kGU&feature=youtu.be Envs10003. (2014c, March 9). W02 c1 Construction Systems [Video file]. Retrieved from https://www.youtube.com/watch? v=8zTarEeGXOo&feature=youtu.be Envs10003. (2014d, March 9). W02 s1 Structural Systems [Video file]. Retrieved from https://www.youtube.com/watch?v=l-JtPpI8uw&feature=youtu.be Envs10003. (2014e, March 9). W02 s2 Structural Joints [Video file]. Retrieved from https://www.youtube.com/watch? v=kxRdY0jSoJo&feature=youtu.be Newton, C. (2014). ENVS10003, BASIC STRUCTURAL FORCES (I) Â [PowerPoint slides]. Retrieved from University of Melbourne, LMS web site: https://app.lms.unimelb.edu.au/bbcswebdav/courses/ENVS10003_2014_SM2/WEEK%2001/Basic %20Structural%20Forces%201.pdf.

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